Sublium : Order bump discount on the first payment only

Order bump discount on the first payment only

/**
 * Plugin Name: Sublium - Order bump discount on the first payment only
 * Description: A Funnel Builder order bump discount on a subscription product applies to the first payment only. Every renewal, whatever the billing frequency, is charged at the full plan price.
 * Version:     1.0.0
 *
 * Install as a must-use plugin (wp-content/mu-plugins/) or as a Code Snippets entry
 * (everything below the opening tag, run everywhere).
 *
 * How it works
 * - Sublium stores the discounted price on the subscription at purchase time and
 *   rebuilds every renewal order from it, so the bump discount repeats forever.
 * - Funnel Builder tags the order line of a bump product with _bump_purchase = yes.
 * - At checkout this snippet also records the full (undiscounted) recurring line total
 *   on that order line; Sublium copies the line meta onto the subscription item.
 * - When any renewal order is built, the line is reset to the full price before
 *   WooCommerce calculates totals and taxes.
 *
 * Subscriptions bought before this snippet was installed have no recorded full price;
 * for those the full price is read from the plan at renewal time instead.
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Full recurring line total (excluding tax) of a plan product, ignoring any bump discount.
 *
 * @param int $product_id Product (or variation) ID.
 * @param int $plan_id    Sublium plan ID.
 * @param int $quantity   Line quantity.
 *
 * @return float|null Null when the price cannot be worked out.
 */
function sublium_bump_first_payment_full_total( $product_id, $plan_id, $quantity ) {
	if ( ! class_exists( '\Sublium_WCS\Includes\Main\Plans' ) || empty( $plan_id ) ) {
		return null;
	}

	// A fresh product object: the one in the cart carries the bump price.
	$product = wc_get_product( $product_id );
	if ( ! $product instanceof WC_Product ) {
		return null;
	}

	try {
		$plan = \Sublium_WCS\Includes\Main\Plans::get_plan_by_id( absint( $plan_id ), $product );
		if ( empty( $plan ) || ! in_array( (int) $plan->get_type(), array( 1, 2, 3 ), true ) ) {
			return null;
		}

		$unit = (float) $plan->get_recurring_cart_price( (float) $product->get_price(), $product );
	} catch ( Throwable $e ) {
		return null;
	}

	if ( $unit <= 0 ) {
		return null;
	}

	return (float) wc_get_price_excluding_tax(
		$product,
		array(
			'price' => $unit,
			'qty'   => max( 1, (int) $quantity ),
		)
	);
}

/**
 * Remember the full recurring line total on the order line of a bump subscription product.
 *
 * @param WC_Order_Item_Product $item          Order line.
 * @param string                $cart_item_key Cart item key.
 * @param array                 $values        Cart item.
 */
function sublium_bump_first_payment_record_full_total( $item, $cart_item_key, $values ) {
	unset( $cart_item_key );

	if ( empty( $values['_wfob_product'] ) || empty( $values['sublium_wcs_plan'] ) ) {
		return;
	}

	$product_id = ! empty( $values['variation_id'] ) ? $values['variation_id'] : $values['product_id'];
	$total      = sublium_bump_first_payment_full_total( $product_id, $values['sublium_wcs_plan'], isset( $values['quantity'] ) ? $values['quantity'] : 1 );
	if ( null !== $total ) {
		$item->add_meta_data( '_sublium_bump_full_total', wc_format_decimal( $total ), true );
	}
}
add_action( 'woocommerce_checkout_create_order_line_item', 'sublium_bump_first_payment_record_full_total', 20, 3 );

/**
 * Charge bump lines at the full plan price on every renewal.
 *
 * @param WC_Order $order Renewal order, before totals are calculated.
 */
function sublium_bump_first_payment_restore_full_price( $order ) {
	if ( ! $order instanceof WC_Order ) {
		return;
	}

	foreach ( $order->get_items() as $item ) {
		// Sublium writes the copied line meta straight to the database, so read it from there.
		$item_id = $item->get_id();
		if ( 'yes' !== wc_get_order_item_meta( $item_id, '_bump_purchase', true ) ) {
			continue;
		}

		$full_total = wc_get_order_item_meta( $item_id, '_sublium_bump_full_total', true );
		if ( '' === $full_total ) {
			$product_id = $item->get_variation_id() ? $item->get_variation_id() : $item->get_product_id();
			$full_total = sublium_bump_first_payment_full_total( $product_id, wc_get_order_item_meta( $item_id, '_sublium_wcs_plan', true ), $item->get_quantity() );
		}
		if ( null === $full_total || (float) $full_total <= 0 || (float) $full_total <= (float) $item->get_total() ) {
			continue;
		}

		$item->set_subtotal( $full_total );
		$item->set_total( $full_total );
		$item->save();
		wc_update_order_item_meta( $item_id, '_sublium_bump_discount_ended', 'yes' );
	}
}
add_action( 'sublium_wcs_renewal_order_before_calculate_totals', 'sublium_bump_first_payment_restore_full_price' );